This invention relates to a method of obtaining a fuel mixture for torches and burners used for welding and cutting.
For more than 50 years, it has been conventional to use acetylene as the fuel for torches and burners for welding and cutting apparatus. The nature of acetylene, however, is such that it is dangerous to store it when compressed and on its own, and it is conventionally stored, after being compressed and dissolved in a solvent such as acetone, in a porous material. Under these conditions the amount of acetylene which can be stored or transported is low relative to the weight of the container and of its contents. Methods have been proposed for the transport and storage of acetylene in liquid form, but pure liquid acetylene is not used, owing to the risk of explosion and the difficulty of handling it.
It has recently been proposed to use acetylene mixtures, which avoid the risk of explosion and can give a sufficiently high combustion temperature for welding and oxygen cutting. These liquid fuel mixtures, which contain from 60 to 10 mols% acetylene and from 40 to 90 mols % ethylene, can be stored or transported at normal temperature in compressed form at a pressure of about 80 kg/cm.sup.2. When the liquid mixture is stored at this relatively high pressure, it has to be supplied in cylinders, usually of low capacity, which means that the cost of using it is relatively high and it cannot be distributed on a large scale by a pipe system.
It is an object of the present invention to provide a method of preparing a fuel mixture comprising from about 10 to about 60 mols % of acetylene and from about 40 to about 90 mols % of ethylene in a form suitable for distribution by pipeline or in bulk by a conventional isothermal tanker lorry, and for storing in a user's tank.